(19)

(11)

EP 3 949 315 A1

(12)

(43) Date of publication: 09.02.2022 Bulletin 2022/06 (21) Application number: 20710571.9 (22) Date of filing: 18.03.2020

(51) International Patent Classification (IPC):  H04L 29/06(2006.01) H04W 12/12(2021.01) H04L 29/08(2006.01) G06F 21/55(2013.01) (52) Cooperative Patent Classification (CPC): G06F 21/55; H04L 63/164; H04L 67/14; H04L 63/061; H04L 63/0272; H04L 63/0428; H04L 63/205; H04L 12/4633 (86) International application number: PCT/EP2020/057536 (87) International publication number: WO 2020/193336 (01.10.2020 Gazette 2020/40)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME Designated Validation States: KH MA MD TN (30) Priority: 27.03.2019 EP 19165365 (71) Applicant: British Telecommunications public limited company London EC1A 7AJ (GB)	(72) Inventor: EL-MOUSSA, Fadi London EC4V 5BT (GB) (74) Representative: British Telecommunications public limited company Intellectual Property Department  9th Floor One Braham Braham Street London E1 8EE London E1 8EE (GB)